Steam-engine.



No. 657,H3. Patented Sept. 4, I900. L. N. HULM.

STEAM ENGINE.

(Application filed Feb. 2, 1900. (No Modei.)

2 Sheets-Sheet l Patented Sept. 4, I900. L. N. HDLM.

STEAM ENGINE.

(Application med Feb. 2, 1900.

2 Sheets-Shae! 2.

Nrrnn STATES PATENT OFFICE.

LABS N. HOLM, OF DES MOINES, IOYVA.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 657,113, dated September 4, 1900.

Application filedI'ehrnary 2, 1900. Serial No. 3,698. (No model.)

To (tZZ whom it YH/[L-Z/ concern:

Be it known that I, LARS N. HOLM, a citizen of the United States, residing at Des Moines, in the county of Polk and State of Iowa, have invented certain new and useful Improvements in Steam-Engines, of which the following is a specification.

The object of this invention is to provide a simple, strong, durable, and inexpensive steam-engine that may be operated by a minimum of steam to produce amaximum of power to the end that an effective engine may be produced at less cost than other engines of corresponding efficiency.

My invention consists in certain details in the construction, arrangement, and combination of the various parts of the engine whereby the object contemplated is attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which- Figure 1 shows a transverse section of the engine through the indicated line 1 1 of Fig. 2. Fig. 2 shows a longitudinal section of the engine through the indicated line 2 2 of Fig. 1. Fig. 3 shows in perspective the shaft and one of the oscillating pistons and the partitions for dividing the two chambers of the engine. Fig. 4 shows a like view of the other piston. Fig. 5 shows in side elevation one of the steam tight packing devices. Fig. 6 shows a plan of same, and Fig. 7 shows in perspective one of the cranks to be attached to the pistonhubs.

Referring to the accompanying drawings, I have used the reference-numeral 10 to indicate a steam-cylinder of ordinary construction and having at its ends the detachable.

heads 11. At the bottom of the cylinder is a base 12, and at the top of the cylinder is an integral fiat-topped extension 13. This fiattopped extension 13 is for the purpose of supporting the steam-chests, which will be hereinafter described. It is to be understood that the cylinder is divided into two equal compartments by a partition which will be hereinafter fully described. In each of the compartments thus formed I have fixed an abutment (indicated by the numeral 14) and extending from a point about thirty degrees from a central line at the top of the cylinder to a point about the same distance from a central line on the opposite side of the cylinder. This abutment is held in position by screws passed through the cylinder, and its central portion is rounded out to admit the hubs of the pistons hereinafter described.

Referring to Fig. 3 of the drawings, the engine-shaft is indicated by the numeral 15 and is of a length to project through both cylinder-heads. Keyed to the central portion of said shaft is a disk-shaped partition 16, having an expansion packing-ring 17 therein. The periphery of this disk is designed to engage the interior of the cylinder. On one end of the shaft is a piston-hub 18, with an integral collar 19 thereon to project through the cylinder head. This hub is keyed to the shaft by means of the key 20, and at its top the piston 21 is formed integrally to project straight outwardly and to extend to the interior surface of the cylinder. This piston is provided with a central openin g 22, into which a packing device is placed. This packing device, which is clearly illustrated in Figs. 5 and 6, comprises two steel strips 23 and 24, each bent at right angles at its central portion and the strip 23 being provided with an extension 25, designed to enter the bifurcated end 26 of the opposite strip. Extensile coil-springs 27 are interposed between the interior of the piston and the outer portions of the said parts 23 and 24:, and like springs 28 are interposed between the piston and the end portions of the parts 23 and 24, so that said parts are normally pressed to their limit of movement in a direction'at right angles to the hub and longitudinally of the hub, and obviously the joint between the parts 23 and 24: may expand Without permitting a leak age of steam at the joint. It is obvious that instead of keying the partition 16 and the hub vice 32, similar to-the packing device in the piston 21, is placed therein. On the extension 19 I have mounted a crank-arm 33, held in place by means of the screws 34, so as to operate in unison with the hub 18. On the extension I have mounted the crank-arm by means of the screws 36, the said shaft 15 being permitted to rotate freely within the crank-arms. This crank-arm 35 is set at an angle of about thirty degrees from the position of the crank-arm 33. At the joints between the cylinder-heads lland the extensions 19 and 30 I have provided the packingboxes 37, of ordinary construction, and the screws 38 provide means for adjusting the packing. Upon the said extension 13 I have mounted the steam-chest 40. This steamchest 40 is divided by a central transverse partition. 41 into two separate chambers, and I have provided means for admitting steam from a boiler direct to these steam-chambers, as follows: The reference-numeral 42 indicates a block supported by screws 43 in the central portion of the top of the chest. A steam-pipe 44 is inserted in a block 45, which is held by means of screws to the block 42, and in this block 42 are thetwo passage-ways 46, leading from the pipe 44 to the steamchambers. It is obvious that by means of the detachable block or plate 45 packing devices may be interposed under the said block or plate to prevent the escape of steam, and this part may be readily detached at any time to adjust the packing.

In each of the steam-chambers within the chest is a D-valve 47, of ordinary construction, each valve being operated by a rod 48, passed through the side of the steam-chest. In the extension 13 are two passage-ways 49, leading from the interior of the steam-chamber to points within the interior of the cylinder at the edges of the block 14, and between these passage-ways is an exhaust-opening 50, leading outwardly toward the ends of the cylinder to points of discharge. The operation of the valve is similar to that of the ordinary reciprocating engine, and in use the steam in the chest will pass downwardly through one of the passage-ways 49 when the D-valve is movedand will force the piston toward the other side of the cylinder. The steam in the other side will then pass upwardly through the remaining passage-way 49 and then outwardly through the exhaustopening 50. Then when the piston reaches the abutment the D-valve will be so operated by mechanism (not shown) as to admit the steam through the passage-way 49 on the side to which the piston is inclined, and by the same process the piston will be returned to its original position. It is obvious that the length of stroke of the pistons may be changed by making the abutment 14 smaller or larger, and, furthermore, the two separate engines on the same shaft may be made to operate on the double-expansion principle by changing the arrangement of supply and exhaust steam pipes, if desired. It is obvious, further, that a double steam-engine made on this principle will have fewer parts, and hence be cheaper to manufacture than the ordinary steam-en gine, and, furthermore, it will be obvious that a maximum of power may be obtained by the use of a given quantity of steam on account of the slight amount of friction necessarily involved in the operation of the engine and on account of the fact that the steam-pressure is applied to the piston at a point distant from the pivotal points thereof. obtained.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States therefor, is=

1. An improved steam engine, comprising in combination, a cylinder, a shaft to pass cen trally through the cylinder, a hub rigidly mounted on one end of the shaft, an exten' sion on the said hub, projected through the cylinder-head, a piston formed on or fixed to the hub, a disk-shaped partition formed on or fixed to the central portion of the shaft, a hub rotatably mounted upon the other end of the shaft within the cylinder, an extension on the hub projected through the other cylinderhead, a piston on the said latter hub, and two abutments fixed in the interior of the cylinder on opposite sides of the central partition, and means for controlling the steam induction and exhaust from the steam-chambers, substantially as, and for the purposes stated.

2. An improved steam-engine, comprising in combination, a cylinder, a shaft rotatably mounted in the cylinder, a hub formed in or fixed to the shaft, a piston on the hub, adiskshaped partition formed on or fixed to the hub, a crank detachably fixed to the hub, asecond hub rotatably mounted on said shaft, a pis ton on said hub, two separate abutments fixed in the cylinder, and means for controlling the passage of steam to and from the cylinder on the opposite sides of said partition.

3. An improved steam-engine, comprising in combination, a cylinder, detachable cylin der-heads thereon, a shaft to pass centrally through the cylinder, a hub formed on or fixed to one end of the shaft, an extension on the said hub to pass through cylinder-head, a crank-arm detachably fixed to said extension, a piston formed on or fixed to the hub, a diskshaped partition formed on or fixed to the central portion of the shaft, a hub rotatably mounted upon the other end of the shaft, an extension on the hub to project through the other cylinder-head a crank-arm detachably secured to said extension, a piston formed on or fixed to said latter hub, and two abutments 14 fixed to the interior of the cylinder on opposite sides of the central partition, and means for controlling the admission of steam to and from the steam-chambers, thus formed, substantially as, and for the purposes stated.

Hence an advantage of leverage is IOQ i. In a steam-engine, the combination of a secured to said block 42, and a steam-inducsteam-chest, a central partition 41 in the tion pipe in the said plate 45, substantially as, steam-chest, a D-valve on each side of said and. for the purposes stated.

partition, a block 42 having the passage-ways LABS N. HOLM. 5 46 therein, detachably secured to the top of Witnesses:

the central portion of the steam-chest, a de- THOMAS G. ORWIG,

tachabie plate 45 in the top of the steam-chest 1 J. RALPH ORWIG. 

